1. Field of the Invention
The present invention relates to an endoscope system for assisting in objectively assessing the outline of a section of an object, which lies at a desired cutting position, using image signals that represent images picked up by viewing the object from a plurality of viewing points.
2. Description of the Related Art
In recent years, endoscopes have been widely employed in the fields of medicine and industries. Generally, an object appears planar in a view image picked up by an ordinary endoscope. It is therefore hard to identify the irregularity or the like in the surface of the object.
Therefore, for example, Japanese Examined Patent Application Publication No. 8-12332 describes a measuring endoscope system for three-dimensionally measuring an object using images picked up by viewing the object from a plurality of viewing points. Moreover, Japanese Patent Gazette No. 2778739 describes a measuring endoscope system that indicates a distance from a reference plane to a measuring point when the reference plane and measuring point are designated, enabling a user to objectively recognize the height or depth of a convex or concave part of an object.
Conventional measuring endoscope systems can measure three coordinates that represent in three-dimensional space a point designated in a reference image, a distance between two points, or a depth from a designated plane.
However, the conventional measuring endoscope systems request a user to designate a plurality of points, and infer the three-dimensional shape of an object of observation from three coordinates that represent each of the points. This poses a problem that it is hard to intuitively grasp the three-dimensional outline of the object of observation.
Moreover, the conventional measuring endoscope systems may adopt a method of acquiring three-dimensional information concerning an entire imaging range from image information so as to create a three-dimensional model. However, this poses a problem that it takes too much time for a computer to perform arithmetic operations required to create the three-dimensional model, making the method is impractical.
Therefore, when the depth of an object, for example, a corroded portion of the inner wall of a pipe must be measured, it takes much time to identify the deepest point.